Crankpin hone



Dec. 20, 1949 P. cs. PlRWlTZ CRANK PIN HONE Filed Nov. 24, 1947 Paul 6. P/r wirz INVENTOR.

Patented Dec. 20, 1949 i l' cMNKP fr fl lG. Ijirwitz f App lication Noqemb'er 24 9 1 Claim. (clisin g,

":The 1' presentiinvention relates to automotive :to'ols "fonuse' in garages. and similar establishments and! has more" particular (reference; to :a

rnovllhandoperated; honejortruing unduly worn -:and out-"of-rdnnd.crankpins. i a 1 'Itis a matter of common knowledge ,thatautomobilamechanicsaare called upon to recondition aridrestoreirregularly worn crank pins in order to provide aasmoothvandn-reliable operating connection between the same and coacting connectiii' g 'rods5 =rdinarily insetting out'to 'abrade or otherwise resurface a distorted crank'pin, the entire crankshaft-.isrremoved "by thev mechanic. Manifestly, when it becomesnecessary to dismantle'the motor in order-to'remove and replace :a -damagedfcrankshaft; considerable time, labor 'taind monetary expenseis-"involved. Because :of these "and dther "objectionable "circumstances; I have evolved andconstructed-'a 'simple andpraic- *tical' manually operable tool for cut-ting and honing the bearingaccommodation surface of a crank pin, said tool"being"novel in that it may be applied and used withoumnecessitatingremoval -onthecnankshaftfronrits beanings. K

More specifically, my invention appertains to a simple sectional clamp, the sections of which are adapted to embrace a crank pin, said sections being provided with circumferentially spaced abrading stones for contact with the crank pin, and handle means being provided for oscillating and working the clamp back and forth until the damaged surface is restored to its original form and shape.

Another object of the invention is to provide a readily applicable and removable clamping head which has effectively functioning coarse and fine surfacing stones and which is constructed to accommodate a shiitably usable handle permitting desired results to be achieved with ease and satisfaction. Q

Other objects and advantages will become more readily apparent from the following description and the accompanying illustrative drawings.

In the drawings:

Figure 1 is a view in elevation of the crank pin hone showing the same applied and ready for use on the crank pin, the latter appearing in section.

Figure 2 is a bottom plan view of the structure seen in Figure 1 with the handle removed.

Referring now, to the drawings by distinguishing reference numerals, it will be seen that the crank pin in Figure 1 is denoted by the numeral 5 and this is a conventional part of an automobile crankshaft. ,Ihe sectional clamp-type head is denoted by the numeral 6 and this is of two-part clamping; u s;

corresp ndin 1e- The bolt is pivoted swingably, as at l2, between the tea-r art 18 5 and-' tssshan s m va e :be ue nathe laws :8,:1theth ead, d: e .3 s rvin ami a-L a t. a isleriial annular form and iis adapted to be removably collared .arqund the crank .pin. Saidv headis fl a aar a. a e hal -scc an ith sea phone-rend i nmm iai s wwalemen al s. "M h dipfsrthevuppen hal -secti al lbe t i rza rr ad; 1b

to;accommodateaclampinabut M. gc'lheoppositeordefti hand end of-itheylower .ihalfesection, l provided iwith;-spaced.. arallel gears. l5 to accommodate "a hingeknucklea I 6 and-.a hinge :xpin t1 carried by the coasting leftshandv zendqof the upper nhalfssection; I J. i This '-.end-j;.portion,;rofi the half-seetionuis suitably recesseditosaccommodate zthe,npperrprojecting portions of said Jears. which portions are providedw'ith holesilfl toJpermit lthe :pin landaknuckletoebeashifted :toe.change the pivot point and to adjust the positions of the -half-sections toraccommodate work ofvarying diameters.

flhe rpiyoted boltendsnut means at the opposite endso'f thesstructuregi the bolt 9 and nut-14, compensates;-forsadjustments M made at the left hand ends of said half-sections 1 and II.

The respective sections are provided with sockets l9, there being four such sockets and these being at circumferentially spaced equidistant points. The sockets are adapted to accommodate the screw-threaded end portion 20 of a detachable operating handle 2|. The latter has a knurled surface 22 to facilitate gripping and operating same. Obviously, by providing handle attaching facilities around the complete circumference of the head, leverage can be applied to most advantageous points depending on the position of the mechanic while oscillating and Working the hone back and forth.

There is a relatively deep notch 23 provided in the inner peripheral portion of the half-section II and this serves to accommodate a coarse grained cutting stone 24 operable by a feed screw 25 having a tool accommodating head 26. Additional notches 21 and 28 serve to accommodate circumferentially spaced fine finishing stones 29 and 30. There is a similar notch 3| which is diametrically opposite to the first notch 23 and this is provided with a permanently mounted medium stone 32. The coarse fast cutting stone placed between th two fine stones makes it possible to out only on the high spots, thereby making the crank pin perfectly round.

As previously stated the tool disclosed is for truing and resurfacing worn and damaged crank manner.

, pin that has had its surface damaged by a burned out rod or foreign substances which had become lodged in the bearing.

,To use the device, simply loosen the bolt and nut means, open up the half-sections of the clamp and place the clamp around the crank pin in an obvious fashion and then retighten the bolt. Next, the coarse stone 24 is tightened down until it comes into contact with the crank pin. Then the handle is inserted in the most conveniently available socket and the tool is oscillated or worked back and forth in a well known The coarse stone coming between the.

two fine stones will out only on the high spots and it is desirable to go all the way around the surface of the crank pin until all high spots are.

removed. Then the coarse stone is backed away and the fine stones are brought into play and the finishing job is accomplished. Y

I desire to stress the variable and selective positions of the handle and means whereby the handle may be attached to desired points for best leverage.

tor.

A careful consideration of the foregoing description in conjunction with the invention as illustrated in the drawings will enable the reader to obtain a clear understanding and impression of the alleged features of merit and novelty sufficient to clarify the construction of the invention as hereinafter claimed.

Minor changes in shape, size, materials and This feature makes it unnecessary to remove the connecting rod from the mosections adjustably and hingedly connected to one another at corresponding ends, a swingable nut-equipped adjusting and clamping bolt carried by the free end of one of said sections at the end opposite to said hingedly connected ends, the remaining section at the last-named end having lugs with which the nut-equipped swingable end of the bolt is releasably and adjustably connectible, a coarse abrading stone mounted in a recess therefor on the central inner peripheral portion of one of said half-sections, said stone being radially projectable and retractable, a setscrew on said one half-section for adjusting said coarse stone, a pair of duplicate fine finishing stones rigidly mounted on the latter halfsection and situated at equidistant points on opposite sides of the coarse stone, and a single medium coarse finishing stone rigidly mounted on the central inner peripheral portion of the remaining half section and located diametrically opposite to said coarse stone, said sections being externally provided with circumferentially spaced, handle accommodation sockets, and a detachable handle cooperable vwith said sockets, said sockets being circumferentially spaced at equidistant points.

PAUL G. PIRWITZ.

REFERENCES CITED I The following references are of record in the file of this patent:

UNITED STATES PATENTS 

